You don't get Photoshop for free. That would be illegal.
But you can use alternative Freeware softwares that are similar to Photoshop...
Here are a few FREE ones that you can use....
GimpShop : http://www.gimpshop.com/
GimpShop is the absolutely free Photoshop clone, which gives you most of Photoshops features, but in an open source package. It will do nearly everything Photoshop can do without the massive cost. Great if you only need to do the occasional bit of Photoshop work, and don’t want to shell out the whole amount. For Windows & Mac OS X 10.3/10.4, Solaris/SPARC.
PhotoScape : http://www.photoscape.org/ps/main/download.php
It is jam-packed with features, while remaining very easy to use. Photoscape provides several modules including a viewer, editor, batch processor, Raw converter, file renamer, print layout tool, screen capture tool, color picker, and so much more. Easy to use.
mtPaint : http://mtpaint.sourceforge.net/
This program, mtPaint, lets you create "pixel art" and manipulate digital photographs. It presents you with a pixel grid of your picture, at varying zoom levels, so that you can accurately paint or edit it. It works with pressure sensitive graphics tablets, supports multiple layers (More then 100), has numerous brush patterns, user-defined gradients, undo, multiple image clipboards, gamma correction, a variety of effects (eg, invert, greyscale, isometric transformations, edge detect, sharpen, "unsharp" mask, soften, Gaussian blur, emboss, etc), crop, rescaling, screen capture, etc. The program works in Windows and Linux, and is open source, under the GNU General Public License.
Serif PhotoPlus : http://www.freeserifsoftware.com/software/photoplus/
PhotoPlus SE features an export optimizer, editable text, layer effects, layer masks, a red-eye removal tool, special effects, versatile brushes, and photo enhancement tools.
Paint.NET : http://www.getpaint.net/
Paint.NET is an image and photo manipulation program that supports layers, unlimited undo and redo, special effects, drawing tools (tools for drawing shapes, splines, Bezier curves, etc), etc. It runs under Windows 2000, XP, 2003 and Vista. It requires the Microsoft .NET Framework (hence its name).
Paint.COM : http://www.rw-designer.com/image-editor
This image editor lets you create and modify JPG, PNG, BMP and other types of raster images. It supports layers with effects, has many drawing tools that can do gamma-blending and color gradient interpolation, has sub-pixel accuracy, the usual assortment of tools (magic wand, transformation, brushes, rectangles, ellipses, polygons, etc) and filters (drop shadow, blur, bevel, colour corrections, etc), supports PhotoShop plugins as well as customizations using JavaScript, etc.
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